dropmarker{
-moz-appearance:none;
width:16px;
height:16px;
-moz-box-align:center;
-moz-box-pack:center;
border:1px solid transparent;
background-color:transparent;
list-style-image:url("chrome://global/skin/toolbarbutton/dropmarker.png");
-moz-image-region:auto;
padding:1px}

dropmarker[disabled="true"]{
opacity:.5!important;
padding:1px!important}